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The UK government has given the go-ahead to carbon dioxide capture and storage (CCS) schemes worth £22 billion (US$28.6 billion). Critics are insisting that this technology – which involves capturing carbon as it is emitted or taking it back out of the atmosphere, then pumping it into rocks deep underground – is unsafe, unproven and unaffordable. Defenders are responding with painstaking rebuttals.
Could the whole debate be missing the point? I think it is better to focus on the big picture – why we need CCS to work – rather than playing whack-a-mole with every objection to individual projects.
The case for CCS boils down to waste disposal: we are going to make too much carbon dioxide (CO₂), so we need to start getting rid of it, permanently.
By burning fossil fuels and producing cement alone, we will generate more CO₂ than we can afford to dump into the atmosphere to have any chance of limiting global warming to close to 1.5°C – even after accounting for the capacity of the biosphere and oceans to mop it up.
So, we need to start disposing of that CO₂, safely and permanently, on a scale of billions of tonnes a year by mid-century. And the only proven way of doing this right now is to re-inject it back underground.
Keep our options open
The world is not giving up fossil fuels any time soon, and the transition is going to be difficult enough without tying our hands by ruling out using CCS technology.
The questions we should be asking are: will “green hydrogen” – a low-carbon fuel produced from water using renewable electricity – be a cheaper way of dealing with lulls in renewable energy generation than gas-fired power plants fitted with CCS? And, can we get by entirely on recycled steel, and eliminate the use of conventional cement in construction, when steel and cement are notoriously hard to produce without fossil fuels?
If the answer to any of these questions, anywhere in the world, turns out to be “no” – or even “not by 2050” – then we need CCS.
Would taking CCS off the table focus minds and make us abandon fossil fuels faster? Perhaps, but it could equally make us abandon climate targets – ultimately, the most expensive option of all.
We should be conscious of “lifecycle emissions” for all forms of energy – including, for example, green hydrogen made with electricity from solar panels that were manufactured using coal-fired power. The right response is to find cleaner suppliers of solar panels for green hydrogen, and cleaner suppliers of gas for blue hydrogen. The wrong response is to give up on either fuel source.
Nature is maxed out
What about offsetting continued fossil fuel use with nature-based solutions, such as restoring ecosystems and rewilding? Unfortunately, we are already maxing out nature’s credit card.
In the Intergovernmental Panel on Climate Change’s (IPCC) scenarios in which warming is kept close to 1.5°C, we need to eliminate deforestation almost immediately, and restore a cumulative total of 250 billion tonnes of CO₂ to the biosphere over the coming 75 years – by restoring forests and wetlands, for example.
Over the same period, we also need to dispose of four times that amount of CO₂ back underground through various forms of CCS – after slashing the amount of CO₂ we produce by 75%-80%.
We cannot bank on stuffing an additional trillion tonnes of CO₂ into the biosphere over the next 75 years – especially as more Earth system feedbacks emerge and accelerate, whereby carbon stored at the Earth’s surface is re-released to the atmosphere as the world warms, forests burn, and peatlands dry out.
Invest, but invest wisely
To limit global warming to the extent the planet urgently requires, we need a means of permanent CO₂ disposal that does not make further demands on the biosphere. But at the same time as enabling CCS technology, we also need to make sure its availability does not encourage yet more CO₂ emissions.
This is where critics of government policy may have a point. If CCS is widely available and heavily subsidised, will that just encourage individuals and companies to use more fossil fuels? The danger is real, but it doesn’t mean we should abandon CCS. We need to be smart about how it is implemented.
Given the way the first CCS projects were set up by the previous UK government, an initial injection of £22 billion from taxpayers is, by now, the only way to kickstart a CO₂ disposal industry. But this should not become an endless subsidy which allows private industry to keep profiting from selling the stuff that causes global warming, while taxpayers pay for the clean-up.
Fortunately, there is another way. The EU has shown, in its Net Zero Industry Act, how regulation can force the fossil fuel industry to contribute to the cost of CCS without relying on US-style subsidies.
The UK government could make it clear that, by mid-century, anyone selling fossil fuels in the UK will be responsible for permanently disposing all CO₂ generated by their activities and the products they sell.
Pricing in safe CO₂ disposal would make fossil fuels more expensive, potentially adding 5p per kWh to the cost of natural gas over the next 25 years. That’s cheap compared with the cost of just dumping CO₂ into the atmosphere.
It is possible, and even affordable, to ensure fossil fuel use falls to meet our available CO₂ disposal capacity. There again, building a global CO₂ disposal industry from a standing start in only 25 years will be hard.
Fortunately, the UK has the right geology, skills and expertise, as well as a history of innovation in climate policy. It also has a clear interest in getting involved in what should become one of the major industries of the second half of this century. And it has a moral obligation, having pioneered taking fossil carbon out of the Earth’s crust, to join the first wave of countries putting it back.
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Myles Allen receives funding from the Strategic Research Fund of the University of Oxford and the European Commission. He is a member of the Advisory Board of Puro.Earth.
